Improved bridge



dubai gember SAMUEL ENSIGN, OE NEW FRANK-LIN, OHIO.

Letters Patent No. 96,569, dated lNovember 9, 1869. v

IMPROVED BRIDGE.

vThe Schedule referred to in these Letters Patentand making part of the same.

To all whom tt may` concern.- l Be it known that '1, ASAMUEL ENsIcN, of Ne Franklin, in the county of Stark, and State of Ohio, have invented 'a new and useful Improvement in Bridges; and I do herebyr declare that the following is a full, clear, and exact description thereof, which will enable others skilled in the art to make and use the same, reference being had to the accompanying drawings, forming part of this specification.

The object of this invention is to provide certain improvements in the construction of iron. bridges, calculated .to work an economy of construction, both as to cost and inthe disposition of the metal for supporting the greatest possible weight with a given quantity.

'The essential feature of the invention consists in the construction and arrangement of the chords, which are made up of vb ars or slabs of either rolled or castmetal, bolted together and so shaped as to. permit them to be cheaply formed and joined together. An-v A other part of the invention consists in the arrangev ment of the braces, suspension-rods, and posts, and the supporting-blocks for the same, all as hereinafter more fully specified.

Figure 1 represents a side view, partly in elevation, and partly in section, of my improved bridge;

Figure 2 represents an end elevation; -and Figure 3 represents a section of one side, taken on the line x x of tig.` 1.

Similar letters oi' reference indicate corresponding parts.

two interior bars b, -joined together, as shown in crosssection in'ig. 3, and secured by bolts O, having shoulders, against which the inner sidesof the .bars are screwed up tight bythe exterior nuts d.

The said plates a, are so formed Aas to constitute the exterior vertical wall of the chords and the curved tops thereof, the edges of the said plates, when made of two parts, meeting at the centre of the tops of .the chords. l y

The' plates b form. parallel inner walls, extending from below the lower walls ofthe plates d, as high as the vertical parts of the latter, and they are turned outward at the base, to vform substantial bearing-surfaces for the support of the chords.

This method o fconstrnction, as will be seen, is very simple and cheap, and provides the most available arrangement as to the strength of the material,

all the plates may be readily rolled to the form required, and punched to provide vthe holes, or in the caseiof castmetal, they may be moulded in the simplest manner.

I form the chords A of two bars, or it may be one exterior bar, of either rolled or castrnetal a a, .and

yThe supporting-blocks e, for the top of the chords, may have curved bases to tit thecurvature of the tops ofthe chords, and the lower supporting-blocks fmay be otherwise lfitted to the configuration of the bases of the chords.

` To these chords I propose to add upper and lower suspension-rods gh, itted at the ends to the transverse blocks or plates t', supported in angular recesses in the ends of the chords. u

The lower suspension rods are strained over the projecting ends of the posts k, provided withadjusting nuts, and the upper suspension rods are provided with diagonal tension braces Z, looping over theuI and around the posts in a manner to prevent them from slidingtoward the vertical plane of their connection 'with the chords.

Thediagonal braces, in extending from one cho 'd to another, and crossing each other,.are arranged 1n the ordinary way, and. supported at the ends by the blocks e-andf. l,

The posts are provided with support-ingeblocks n, belowl each chord, the lower o nes 'being adjustable by vmeans of screw-threads, and the upper ends of the posts screwed into nuts o, which firmly clamp the vchords between the said upper blocks n and the -are firmly clamped by the braces m.

Having thus described my invention, I- claimas new, and desire to secure by Letters Patent-.

1. The combination, with two' exterior and two interior bars a a and b I1, .shaped as described, of the houldered boltsO, secured by the nuts d, all as set orth. f

2. Theimproved bridge above described, each of its parts being shaped,`titted, and arranged in the structure with respect to the others, as shown and described.

' l SAMUEL ENSIGN,

Witnesses:

' J. R.BEAT1Y, H. C. MARCH. 

